An attorney tasked by Duxbury Public Schools with investigating sexual assault allegations against a former hockey coach said she was left with “serious concerns” about his credibility, particularly when he was asked about his relationship with the middle-school-aged student in question, as well as about a sexual relationship with another teacher. The report, a copy of which was obtained by The Boston Globe, alleges that John Blake didn’t tell the truth when it came to discussing a sexual relationship with another teacher, and when he said he didn’t remember the student he was accused of raping. Advertisement: Joseph and Melissa Foley accused Blake of sexually assaulting their son, Parker, on multiple occasions between 2005 and 2007, and said the abuse only stopped when Parker threatened Blake with a knife, according to the newspaper.